Summary In recent decades, a growing number of low‐income countries (LICs) have experimented with voluntary community‐based health insurance (CBHI), as an instrument to extend social health protection to the rural poor and the informal sector. While modest successes have been achieved, important challenges remain with regard to the recruitment and retention of members, and the regular collection of membership fees. In this context, there is a growing consensus among policymakers that there is a need to experiment with mandatory approaches towards CBHI. In some localities in Tanzania, local actors in charge of community health funds (CHFs) are now relying on what is best described as quasi‐mandatory enrolment strategies, such as increasing user fees for non‐members, automatically enrolling beneficiaries of cash transfer programmes and enrolling the exempted groups (people who are entitled to free healthcare). We find that, while these quasi‐mandatory enrolment strategies may temporarily increase enrolment rates, dropout and the non‐payment of contributions remain important problems. These problems are at least partly related to supply side issues, notably to inadequate benefit packages. Overall, these findings indicate the limitations of any strategy to increase enrolment into CBHI, which is not coupled to clear improvements in the supply and quality of healthcare.